This one is not quite a resignation, but still one of the most hilariously honest good-byes in corporate history. In 2013, the former CEO of Groupon, Andrew Mason, penned a company-wide e-mail that began:

"People of Groupon,

After four and a half intense and wonderful years as CEO of Groupon, I've decided that I'd like to spend more time with my family. Just kidding — I was fired today. If you're wondering why... you haven't been paying attention."

Mason took full responsibility for Groupon's financial fall from grace. When the company went public in 2011, it was a Wall Street darling, leading a pack of hugely popular "daily deal" Web sites [source: Agrawal]. Groupon had millions of subscribers who signed up for daily e-mails advertising steep discounts at local businesses like restaurants and nail salons. But when merchants grew frustrated with Groupon's hefty fees, they backed out, leaving the company to scramble for a new business model.

Mason had ample reason to leave with a smile. He cashed in tens of millions of dollars after the 2011 initial public offering and remains a 7 percent shareholder in Groupon, which is still worth hundreds of millions on paper [source: Lappin]. In one of the weirder post-resignation-CEO twists, Mason released a rock album in July 2013 called "Hardly Workin'," a compilation of original songs he describes as "motivational business music targeted at people newly entering the workforce" [source: Feigerman]. Sadly, this one's not a joke.